Phonatory Demarcations of Intonation Phrases in Bulgarian

Vowel devoicing at phrase boundaries is shown to depend on sentence mode (statement, question) and information structure (non-contrastive vs. contrastive and broad vs. narrow focus), which affect the type of nuclear accent and boundary tone. In li-questions, considerably less devoicing of the vowels before the phrase boundary is found than in other conditions, because the rising boundary contour prevents devoicing. In all other conditions, mode and information structure only affect the realisation of the vowel in the two syllables before the phrase boundary if the nuclear accent is realised on the last content word of the phrase, just before the boundary. In these position, the differences in observed vowel devoicing can also be related to the intonational properties of the utterance, namely to the accent type. In particular, the peak alignment of the accent explains the presence or absence of voicing, or better the amount of devoicing, since it is clearly a gradient phenomenon. In general, the earlier the peak, the greater the tendency towards devoicing.